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1.
Two distinct chickpeas of the domestic chickpea, C. arietinum L., exist and are referred to as ‘desi’ or microsperma and ‘kabuli’ or macrosperma. Cicer reticulatum Ladiz. is considered to be the wild progenitor of the domestic chickpea. However, the morphological variation in 18 original accessions of C. reticulatum is narrower than those of the domestic chickpeas. The aim of the study is to increase the variability in C. reticulatum. In M2 generation, a mutant with white flower color was isolated despite of the fact that the parent has the pink flower. Although seed coat color of the parent was dark brown, the mutant was cream like ‘kabuli’ chickpea. It is commonly accepted that the large seeded domestic ‘kabuli’ chickpeas originated from the small seeded ‘desi’ chickpeas, but the induced mutants (white flower and cream seed coat color) of C. reticulatum may suggest an additional path for the evolution of ‘kabuli’ chickpea. ‘Kabuli’ chickpeas could have originated from spontaneous mutants of C. reticulatum. In M3 generation, multipinnate leaf, erect growth habit, green seed and double-podded chickpeas were isolated. Among these progenies, morphologic variability increased and approached domesticated chickpea. Based on historical records and the induced mutants obtained from this study, the domestic ‘kabuli’ chickpea could have directly emerged from C. reticulatum in ancient Eastern Turkey.  相似文献   

2.
Seven primitive races ofGossypium hirsutum L.punctatum, marie-galante, richmondi, latifolium, morrilli, palmeri, mexicanum and five F1 crosses were inoculated withFusarium f. sp.vasinfectum physiological strain I. in the wilt field of Cixi Cotton Institute in 1987. There were highly significant differences among these primitive races.Punctatum andpalmeri were highly resistant. The resistances ofmarie-galante andmexicanum was similar with that of cultivar ‘Simian2’;richmondi, latifolium andmorrilli were susceptible. The disease incidence of F1 in five primitive races hybridized with cultivar ‘Simian2’ was generally higher than that of mid-parent value. Inheritance of wilt resistance was partially dominant. In addition, 178 accessions of eight primitive races were evaluated for their resistance as before in 1989. There were significant differences in resistance among races and intra-race accessions. There were wilt resistance accessions among primitive races in which disease incidence was below 10%–25%. Inpalmeri, marie-galante, richmondi andpunctatum, one accession was immune with 0% disease incidence, respectively; 22.7–77.4% accessions were susceptible with 50% disease incidence. It showed that primitive races were mixed populations. They should be evaluated and screened for their utilization in cotton breeding program. Some best plants were selected from F2 of two crosses, ‘Simian2’ ×palmeri and ‘Simian2’ ×mexicanum, based on the resistance toFusarium wilt and the response to photoperiod. 11 lines had been obtained with good fiber quality and relatively high potential production by backcrossing improvement. These lines are now being tested.  相似文献   

3.
A PCR (polymerase chain reaction) amplification method using newly designed S-RNase primers was carried out in five Korean-bred pear cultivars and ten Japanese-bred pear cultivars. A new S-RNase allele, designated as S10, was discovered from ‘Chengsilri’, containing a 1513 bp and two exons (213 bp in total) that coded for a peptide of 71 amino acids. The S10-RNase allele contained the three conserved cysteine residues peculiar to S-RNase in Japanese pear and one histidine residue essential for RNase activity. We compared nucleotide sequence similarity of the exon regions of ten pear S-RNase alleles. The nucleotide sequence of S1 showed a high similarity to S4 (97.4%) and the new S10 shows 77.8% (S5) to 84.4% (S4) similarity with the other pear S-RNase alleles. S10 had a unique restriction endonuclease site for ‘HhaI’, with digests yielding fragments of 1235 and 491 bp. The S-genotype of pear cultivar (‘Chengsilri’) was determined to be S5S10 by PCR–RFLP (restriction fragment length polymorphism). Cluster analysis of 49 known S-RNase alleles of the Rosaceae separated into two divergent groups are as follows: group I: pear and apple, group II: almond, sweet cherry and mume.  相似文献   

4.
In order to give insights into the origin and historical selection process of Tunisian apricot propagated by grafting, 31 cultivars from three areas presenting contrasting ecological conditions – Kairouan, Testour and Ras Jbel were compared to cultivars from Europe, North America, North Africa, Turkey, Iran and China, using 234 AFLP markers. The phenetic analysis allowed to distinguish 5 clusters, the four previously defined groups: – ‘diversification’, ‘geographically adaptable’, ‘continental European’ and ‘Mediterranean’ – groups and the Tunisian one. The partitioning of genetic diversity within and between cultivar groups assessed according to the Bayesian approach and assuming Hardy–Weinberg equilibrium, showed a loss of 21.81–38.49% of genetic diversity in Tunisian apricot compared to Mediterranean and diversification groups, respectively. Genetic variation occurred within Tunisian subgroups rather than among (FST = 0.060) evidencing a narrow genetic pool. Mediterranean and Tunisian groups were the least differentiated. Comparing them, 24 AFLP fragments discriminated the Mediterranean group from the Tunisian group but most of them where also shared by the other groups. Strongly differentiated gene pool and low genetic diversity are probably the result of bottleneck effects linked to the occurrence of propagation by seedlings rather than by grafting during the introduction periods in the North and the Centre of Tunisia. This study points at the propagation by seedlings as an important factor which should be taken into account to understand the evolution of apricot in South Mediterranean areas.  相似文献   

5.
A study has been conducted into the genetic variation analysis of the tetraploid asparagus landrace ‘Morado de Huetor’ and its relationship with current commercial cultivars using Random Amplified Polymorphic DNA (RAPD) molecular markers. The presence of different ploidic levels in the ‘Morado de Huetor’ landrace has been also studied using cytogenetic analysis. Ten decamer oligonucleotides were used to obtain RAPD markers and to characterise 52 individuals of ‘Morado de Huetor’, 7 of the tetraploid cultivar ‘Purple Passion’, and 55 of 5 diploid hybrid commercial cultivars. Jaccard similarity index was calculated and a cluster analysis using UPGMA (Unweighted Pair-Group Method using Arithmetic Average) was performed. Tetraploid asparagus, ‘Morado de Huetor’ and ‘Purple Passion’, were well differentiated from the diploid ones showing a higher genetic variability. This result suggests a different origin for tetraploid and diploid asparagus varieties. Within the diploid cultivars a variety distribution was obtained. A specific monomorphic band (OPB20883) was found in tetraploid varieties. Within the diploid cultivars, two bands (OPB20830, OPC15705) can be used to distinguish between the hybrid cultivars used in this study. Tri-, penta-, hexa-, and octoploid plants were found in ‘Morado de Huetor’. The origin of these ploidic levels is discussed and their use in the development of new varieties is proposed. In conclusion, ‘Morado de Huetor’ is a genetic resource that could be used to increase the narrow genetic background reported in diploid asparagus cultivars.  相似文献   

6.
For the selection of donors with valuable characteristics for breeding, 39 thyme accessions were evaluated in three years according to a staggered schedule. The criteria investigated were: winter hardiness, beginning of flowering, growth height, yield of the dry herb, content of essential oil, composition of the essential oil, DNA content of cell nuclei and number of chromosomes. The most strongly varying traits between the populations were the yield of dry herb, the content of essential oil and the content of volatile phenols with coefficients of variation (CV) between CV 40% and 50%. The largest variation within a population was detected for the yield of dry herb (CV 25–46%) and the content of essential oil (CV 17–48%). The homogeneity of the populations was different. The minimal average coefficient of variation of all traits (CV 19%) was determined in the population of the cultivar ‘Varico II’ and in a population from Lithuania. The ploidy level of T. vulgaris was diploid (2n = 30).  相似文献   

7.
Common bean (Phaseolus vulgaris L.) was introduced in Europe from both Mesoamerican and Andean centres of origin. In this study, a collection including 544 accessions from all European regions showed that the Andean phaseolin types ‘T’ (45.6%) and ‘C’ (30.7%) prevailed over the Mesoamerican ones ‘S’ (23.7%), and accessions with cuboid seed shape (34.9%), maroon coat darker colour seed (44.3%), uniform seed colour (69.6%) were the most frequent. European accessions with phaseolin ‘S’ showed a significantly larger average seed size compared to those from America in the same phaseolin class while those presenting ‘T’ and ‘C’ phaseolin did not. This suggests that, during crop expansion in Europe, sampling or selection favoured the large-seeded races within the Mesoamerican ‘S’ gene pool or, possibly, introgression from Andean germplasm did occur. A core collection was developed using sampling approaches based on the information available in the genebank databases and on phaseolin patterns. Four sampling strategies were used: simple random sampling, and three random-stratified samplings, by logarithm of frequency of accessions by country, by European region, and by phaseolin pattern, respectively. Two sampling strategies resulted in core collections significantly different for phaseolin electrophoretic patterns from the whole collection. Stratification by phaseolin patterns increased the frequency of ‘S’ types (‘C’ type = 33%, ‘T’ type = 5.7% and ‘S’ type = 31.3%). The core collections were validated using seven seed characters, and no significant difference was observed in all strategies. This first developed European bean core collection will help to assess the contribution of the two American gene pools to the European germplasm and their relative importance for breeding purposes.  相似文献   

8.
Plant breeders are interested in strawberry species as donors of volatile compounds in breeding programmes because of the diversity and intensity of wild strawberry aroma. Therefore, the topic of this paper is the prospective analysis of four accessions of four wild strawberry accessions in comparison to a standard cultivar of Fragaria × ananassa Duch. by using human sensory, gas chromatography mass spectrometry (GCMS) and gas chromatography–olfactometry (GCO). The wild species have higher aroma intensities compared with the cultivated one. The flavour quality differs significantly. Semiquantitative GC analysis revealed that F. × ananassa cv. ‘Elsanta’ has the lowest content of volatile compounds whereas Fragaria moschata L. ‘Cotta’ has the highest. The aroma impressions, measured by GCO, support the findings of GCMS analyses. The nasal impact frequency (NIF)-profiles of the wild types are more manifold and of higher intensities than those of the cultivated F. × ananassa cv. ‘Elsanta’ which corresponds with the overall flavour impression when tasting the fresh fruits.  相似文献   

9.
Portuguese wheat landraces, ‘Arrancada’ were collected from the Aveiro region, Portugal before the 1950s. We found in eight accessions of `Arrancada' hexaploid wheat with the long glume phenotype. We assessed the comparative genetic diversity among Portuguese `Arrancada' wheat and Triticum petropavlovskyi Udacz. et Migusch. using AFLP assays and discuss the origin of long glumed `Arrancada' wheat. With the four primer pairs a total of 4885 visible bands were scored corresponding to 99 AFLP markers as putative loci, of which 55 markers (54%) were polymorphic. UPGMA clustering and PCO grouping showed that long glumed ‘Arrancada’ wheat and T. petropavlovskyi were genetically diverse. Long glumed ‘Arrancada’ hexaploid wheat separated into two clusters (groups) in both the UPGMA dendrogram and in PCO analysis. Four long glumed accessions fell in the cluster of tetraploid wheat. A similar argument could be made for another four accessions which belong to the cluster of hexaploid wheat. The substantial level of genetic variation indicated that long glumed ‘Arrancada’ wheat and T. petropavlovskyi originated independently. It is most likely that the P-gene of long glumed ‘Arrancada’ hexaploid wheat was introduced from T. turgidum ssp. polonicum (L.) Thell. to T. aestivum via natural introgression or breeding. We suggest that the long glumed ‘Arrancada’ hexaploid wheat did not originate from T. aestivum through spontaneous mutation at the P locus  相似文献   

10.
Using survey data from Jala, Mexico, this case-study evaluates in situ maize conservation of the variety ‘Jala’ (Zea mays L.). Though historically ‘Jala’ was the dominant variety grown in the valley of Jala, today less than 20% of farmers grow it on only 5% of the maize area. Younger growers of the ‘Jala’ variety specialize in it, growing relatively large amounts for niche markets. Older, diversified farmers grow small areas for household use and to compete in a local contest. Conservation of the ‘Jala’ variety has been heavily influenced by shifting ideal concepts of maize, as determined by market and consumption demands and by a contest designed to promote in situ conservation. The current move away from nationalized purchasing may favor ‘Jala’s’ continued conservation.  相似文献   

11.
‘Domestication’ is a traditional farmers’ practice reported for yams (Dioscorea sp.) in Benin (West Africa). It involves introducing ‘spontaneous’ (naturally occurring) yams, supposedly wild (D. abyssinica and D. praehensilis), in varieties of the D. cayenensis–D. rotundata cultivated species complex. In this study, we established the genetic nature of ‘predomesticated’ yam plants using the amplified fragment length polymorphism (AFLP) technique. A total of 213 accessions, consisting of 32 predomesticated yams, 70 D. cayenensis–D. rotundata, 86 D. abyssinica and 25 D. praehensilis yams were analysed. Using 91 AFLP markers, three groups of accessions were distinguished, broadly corresponding to the above botanical species. Of the 32 predomesticated accessions, 16% were clustered with D. praehensilis, 37% with D. abyssinica and the remaining 47% with D. cayenensis–D. rotundata. These results demonstrated the use of wild plants by farmers in their domestication process, and suggested that plants derived from intervarietal and interspecific hybridisation may also be subject to this process. This study has shown that through domestication farmers influence and increase the genetic diversity in yam by using sexual reproduction of wild and possibly cultivated yams.  相似文献   

12.
Information regarding the amount of genetic diversity is necessary to enhance the effectiveness of breeding programs and germplasm conservation efforts. Genetic variation between 21 switchgrass genotypes randomly selected from two lowland (‘Alamo’ and ‘Kanlow’) and one upland (‘Summer’) synthetic cultivars were estimated using restriction fragment length polymorphism (RFLP) markers. Comparison of 85 RFLP loci revealed 92% polymorphism between at least two genotypes from the upland and lowland ecotypes. Within ecotypes, the upland genotypes showed higher polymorphism than lowland genotypes (64% vs. 56%). ‘Kanlow’ had a lower percent of polymorphic loci than ‘Alamo’ (52% vs. 60%). Jaccard distances revealed higher genetic diversity between upland and lowland ecotypes than between genotypes within each ecotype. Hierarchical cluster analysis using Ward's minimum variance grouped the genotypes into two major clusters, one representing the upland group and the other the lowland group. Phylogenetic analysis of chloroplast non-coding region trnL (UAA) intron sequences from 34 switchgrass accessions (6 upland cultivars, 2 lowland cultivars, and 26 accessions of unknown affiliation) produced a neighbor-joining dendrogram comprised of two major clusters with 99% bootstrap support. All accessions grouped in the same cluster with the lowland cultivars (‘Alamo’ and ‘Kanlow’) had a deletion of 49 nucleotides. Phenotypic identification of greenhouse-grown plants showed that all accessions with the deletion are of the lowland type. The deletion in trnL (UAA) sequences appears to be specific to lowland accessions and should be useful as a DNA marker for the classification of upland and lowland germplasm.  相似文献   

13.
Dead seeds of a fodder beet cultivar ‘Elvetham’ stored under ambient conditions since 1880 were compared to a homonymous sample preserved in an on-farm situation in Denmark. DNA was isolated from single seeds and successfully applied to Amplified Fragment Length Polymorphism (AFLP) analysis of the accessions. Six primer pairs were used to determine the similarity between the two accessions based on 112 polymorphic bands. Furthermore, similarity among seven cultivars of fodder beets representing the main types used in Scandinavia at the end of the 19th century was determined. This analysis was based on 152 polymorphic bands. Differentiation among the seven cultivars was determined to a mean G ST value of 0.438, while G ST between the two ‘Elvetham’ accessions was 0.266. A principal coordinate analysis based on jaccards similarity index illustrates that the two ‘Elvetham’ accessions are different from each other. The differentiation is higher than the value found between two separate ‘Eckerndorfer’ accessions. The results indicate that the cultivated accession has changed. Additionally, the value of applying old dead seed material for documentation in gene banks is demonstrated. During the analysis it was found that DNA isolated from seeds and leaves behaved differently in the AFLP process, however, the two fractions assigned to their common accession.  相似文献   

14.
Wild soybean (Glycine soja), the progenitor of soybeans, has become an important germplasm source for soybean breeding. The Chinese G. soja germplasm collection includes two subcollections, one typical wild soybean (G. soja) and the other ‘big seed type’ (semi-wild soybean, G. gracilis). In order to understand the nature of this big seed type subcollection, a considerable number of 1,185 accessions were investigated focusing on phenotypes, compositional structure and genetic diversity of this subcollection. The results showed that there were 617 combined morphotypes formed by six major morphological traits. The morphotype number and diversity gradually decreased among four sections from small to large 100-seed weight sizes. The big seed subcollection accumulated distinctly high frequencies for white flower, grey pubescence, seed non-bloom and four seed coat colours (green, yellow, brown and black), differing from the typical G. soja. Between the two subcollections, only the compositional structures of leaf shapes were almost in agreement. A rare strip-shaped leaf only appeared in typical G. soja and small-seeded grade (100-seed wt) of the big seed type. Seed non-bloom trait showed that the increased frequencies were concomitant with the augmenting of 100-seed weight. The data suggested that white flower accumulated rapidly in the big seed type, followed by seed non-bloom, while the slowest rate of accumulation was grey pubecence, and that the ‘large-seeded type (2.51–3 g 100-seed wt)’ of typical G. soja and the ‘smallest-seeded type (3.01–3.5 g 100-seed wt)’ of the big seed type could have a closer genetic relationship. The morphotype number and genetic diversity showed reduced values with increased 100-seed weights. The geographical distribution of genetic diversity indicated two tendencies: decreased from north to south and also from east to west. Our results suggested that Northeast China was the first centre of morphological diversity for the big seed type, and the North was the secondary centre in China.  相似文献   

15.
Behavioural changes are used as early warning systems for water quality monitoring or as rapid and sensitive endpoints in toxicity bioassays. In this study, the automated measurement of behavioural patterns of the thrichopteranHydropsyche angustipennis (Curtis 1834) has been recorded for the first time in sediment with the Multispecies Freshwater Biomonitor, MFB. The MFB recorded different types of behaviour in sediment with the same accuracy as in water. Behavioural differences of the larvae exposed to ‘water only’ and ‘sediment only’ have been described. In ‘choice’ experiments, the larvae preferred the ‘water only’ compartment.  相似文献   

16.
The ‘Morelos’ accessions of Amaranthus from Mexico demonstrate taxonomic ambiguity at the basic morphologic level. The main cause is the enormous morphological and genetic variation exhibited by the species in the genus. Although basic morphological criteria can be applied to herbarium specimens or germplasm collections for quick taxonomic identification, the morphological data alone can be misleading. To ascertain the taxonomic identity of the ‘Morelos’ accessions and their hypothesized species affiliation to Amaranthus caudatus or Amaranthus cruentus, we conducted a comparative analysis of phylogenetic relationships among these taxa/accessions using amplified fragment length polymorphism (AFLP) and micromorphology methods. Based on AFLP data, all the controversial ‘Morelos’ accessions can be consistently placed into a single A. cruentus species clade, which is clearly separated from the A. caudatus species clade. The AFLP-based phylogenetic relationship of ‘Morelos’ and delimitation of A. cruentus and A. caudatus are further supported by micromorphology, showing that the combination of these techniques can provide more reliable data for germplasm identification than each method used alone.  相似文献   

17.
Vigna vexillata is considered as a pantropical distributed wild species closely related to the cowpea (Vigna uniculata) and adapted to infertile soils. The species is occasionally used for its storage roots as well as forage and erosion control plant. The objective of this study was to pursue personal communications that V. vexillata has be transformed into a cultivar in Indonesia. Seven Indonesian islands were visited (Java, Bali, Sumba, Flores, Timor, Kalimantan and Sulawesi). Wild V. vexillata was found in Java, Bali, Sumba, Flores and Timor, occasionally used as wild ‘forest food’, and cultivated V. vexillata was found in Bali and Timor, Seven cultivars were collected and two of these were made available for the National Botanic Garden of Belgium. The cultivars were primarily cultivated for their storage roots, propagated by seeds, required no scarified seeds for good germination and formed non-dehiscent pods. On-farm root yields of 18–30 t ha−1 and seed yields of 0.7–1.2 t ha−1 were estimated. A brief discussion about the common names of wild V. vexillata is given and it is proposed to use the name ‘tuber cowpea’ for V. vexillata accessions which are cultivated for their storage roots. The material may be of interest for regions, where the growing season is too short or the rainfall too low for sweet potato and cassava as well as to incorporate cultivar characteristics into wild V. vexillata accessions which are used for their storage roots.  相似文献   

18.
The difficulty and problems encountered in the study of cultivated plants, in general and sugarcane, in particular has been indicated. In order to understand these problems, a brief review on the taxonomy of Saccharum and closely related taxa, namely, Erianthus, Sclerostachya, Narenga and Miscanthus (generally known as ‘Saccharum complex’) has been given. A short account on the important morphological features that are specific to sugarcane has also been stated as classification is commonly based on such morphological characters. A note has been added on the chromosome number, origin, and distribution of the species of ‘Saccharum complex’ members. Taxonomic keys have been devised for identification of the genera of Saccharinae and for the species of Saccharum and Erianthus occurring in India. A new combination, Sclerostachya fallax (Balansa) Amalraj et Balasundaram, has also been proposed.  相似文献   

19.
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20.
A cultivated tetraploid asparagus landrace ‘Morado de Huetor’ growing in the South of Spain has been collected and conserved ex situ in two experimental plots. This landrace has been reported to have an interspecific hybrid origin (A. officinalis × A. maritimus). A 59% of the total farmer plots cultivated in the region were visited and ripe fruits collected from 10 female plants per plot. Fruits from a total of 300 plants were collected and two half sibs descendents from each one were sown separate in two plots. Of the 88 farmer plots visited, the landrace was growing only in 34, in the rest the crop had been removed. Hence, ‘Morado de Huetor’ is in a very high risk of disappearing. Now this landrace is conserved ex situ in two experimental plots with sufficient number of plants to represent their maximum variability in order to be used in plant breeding.  相似文献   

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